164It is clear from the provisions of Articles 44(1)(c) and 48(2) of the Rules of Procedure of the Court of First Instance, taken together, that the application initiating proceedings must indicate the subject-matter of the dispute and set out in summary form the pleas raised and that no new plea in law may be introduced in the course of proceedings unless it is based on matters of law or of fact which come to light in the course of the procedure. The fact that the applicant became aware of a factual matter during the course of the procedure before the Court of First Instance does not mean that that element constitutes a matter of fact which came to light in the course of the procedure. A further requirement is that the applicant was not in a position to be aware of that matter previously (Case T-139/99AICS v Parliament [2000] ECR II-2849, paragraphs 59 and 62).